At sixty centimetres wide and a little over a metre in height, the stone-built passage demands a particular kind of commitment from anyone curious enough to explore it, and that combination of confinement and careful construction is precisely what makes it interesting.

The structure is a souterrain, a type of underground passage and chamber built during the early medieval period in Ireland, typically associated with ringforts and cashels and thought to have served for storage, refuge, or both. The cashel here, a circular stone-walled enclosure of the kind common across Munster, provides the broader context. The souterrain itself was first noted by Hartnett in 1939, and a more detailed account was provided by McCarthy in 1977. That account gives us the specific dimensions: a passage running 3.6 metres in length, roofed with flat stone lintels laid across the top, which opens at its south-western end into an oval chamber measuring roughly 1.82 metres by 1.52 metres. The chamber departs slightly from the construction method of the passage; where the passage is fully stone-built, the chamber roof is cut from the earth itself, a transition that hints at the practical decisions made by whoever built it, working with the ground as much as against it.